Vibrating beam force transducers are used as force sensing elements in sensor instruments, such as accelerometers and pressure sensors. It is often advantageous to design these sensors using two vibrating beam transducers such that the quantity being sensed, e.g., acceleration or pressure, forces one transducer in tension and the other in compression. The purpose of this arrangement is to reduce errors by canceling common mode errors, such as even order nonlinearities, bias temperature sensitivity, clock sensitivity, bias aging drift, and pressure sensitivity. However, this method of error cancellation is only effective to the extent that the two force sensing elements experience the same force loading by the quantity being sensed. If the two force sensing elements do not share equal and opposite force loading, then sensor accuracy is compromised.
A common method of accomplishing this in force transducer systems is a push-pull arrangement in which the force sensing elements are subjected to forces in opposite directions. However, problems arise when the push-pull arrangement is implemented in a physical device. For example, to utilize push-pull force sensing elements in a pendulous accelerometer, two force sensing elements are both connected to a common proof mass. The force sensing elements typically extend either perpendicular to or parallel to the pendulous axis of the accelerometer. However in such a configuration, any thermal expansion mismatch between the support/proof mass assembly and the force sensing elements creates thermal strains that in turn create large common mode error signals that can only be partially suppressed by signal processing techniques. As a result, the force sensing elements should be physically matched in all sensitivities, in order to provide a high level of common mode rejection. This close matching is often difficult to achieve.
Therefore, devices and methods for overcoming these and other limitations of typical state of the art sensor instruments are desirable.